document.write( "Question 1153397: If a number is added to the numerator of
\n" ); document.write( "7
\n" ); document.write( "8
\n" ); document.write( " and twice as much is added to the denominator, the result is
\n" ); document.write( "8
\n" ); document.write( "13
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\n" ); document.write( " Find the number.
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Algebra.Com's Answer #775608 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!

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\n" ); document.write( "\n" ); document.write( "old numerator = 7 \r
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\n" ); document.write( "\n" ); document.write( "new numerator = 7+x\r
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\n" ); document.write( "\n" ); document.write( "old denominator = 8\r
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\n" ); document.write( "\n" ); document.write( "new denominator = 8+2x, since twice as much is added here\r
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\n" ); document.write( "\n" ); document.write( "old fraction = \"7%2F8\"\r
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\n" ); document.write( "\n" ); document.write( "new fraction = \"%287%2Bx%29%2F%288%2B2x%29\"\r
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\n" ); document.write( "\n" ); document.write( "new fraction = \"8%2F13\" (given info)\r
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\n" ); document.write( "\n" ); document.write( "Set \"%287%2Bx%29%2F%288%2B2x%29\" equal to \"8%2F13\". Solve for x.\r
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\n" ); document.write( "\n" ); document.write( "\"%287%2Bx%29%2F%288%2B2x%29+=+8%2F13\"\r
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\n" ); document.write( "\n" ); document.write( "\"13%287%2Bx%29+=+8%288%2B2x%29\" Cross multiply\r
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\n" ); document.write( "\n" ); document.write( "\"91%2B13x+=+64%2B16x\" Distribute\r
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\n" ); document.write( "\n" ); document.write( "\"91-64+=+16x-13x\" Separate out common or like terms. \r
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\n" ); document.write( "\n" ); document.write( "\"27+=+3x\" Combine like terms\r
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\n" ); document.write( "\n" ); document.write( "\"3x+=+27\"\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+27%2F3\" Divide both sides by 3\r
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\n" ); document.write( "\n" ); document.write( "\"x+=+9\" This is the answer.\r
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\n" ); document.write( "\n" ); document.write( "Using that x value, we can see that,\r
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\n" ); document.write( "\n" ); document.write( "new numerator = 7+x = 7+9 = 16
\n" ); document.write( "new denominator = 8+2x = 8+2*9 = 26\r
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\n" ); document.write( "\n" ); document.write( "new fraction = \"%287%2Bx%29%2F%288%2B2x%29+=+16%2F26+=+%282%2A8%29%2F%282%2A13%29+=+8%2F13\"\r
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\n" ); document.write( "\n" ); document.write( "The answer is confirmed.\r
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\n" ); document.write( "\n" ); document.write( "Answer: 9\r
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